[paul s.]

Torque is a byproduct of displacement, cylinder pressure, and volumetric efficiency. Peak torque rpm correlates to airspeed in the port and that speed is in the range of 250fps.

[tpssonic]

Will:

Torque is proportion to displacement was the given in what I was saying. If you increase the torque and but don't change the the bore, volumetric efficiency, head and exhaust characteristics, etc. (i.e. all other things being equal) the displacement -and the torque- will increase AND (this was my main point) the peak torque WILL OCCUR AT A LOWER RPM (but higher piston speed).

That being said, if there is some (major) restriction in fuel flow or exhaust flow that will effectively hit a ceiling at some torque/hp level, then the comparison (i.e. stroke as the limiting factor of torque) is flawed and all bets are off the the table.

Tony

[chuckies76ta]

Originally Posted by Firebob

All other things being equal( as much as possible), I was wondering. Seen lots of sheets for 455 dyno pulls but I don't think I've ever seen any dyno numbers for a stroker.

I have a 400 stroker in my T/A and my wife's 68 F/B is a 455 stroked.
The 400 dynoed at 560 h/p and 580 torque, The 455 dynoed at 590 h/p and 600 torque. Both have same KRE D-port heads from SD Performance.
Both engines have SD Performance cams. The 400 has hydraulic lifters with 236/245.
The 455 has solid lifters with 246/252.

My wife has run a best of 10.90 with her car weighting 3700 pds, Th400, 3.24 gear, and full 3" exhaust.

Charles

[tpssonic]

chuckies76ta:

Very nice numbers. At what rpm does the 455 make peak hp? Peak torque?

Is the 236/245 on a 112 LSA? It seems like the peak torque (4500) is a bit higher than I've see for the OF cam, but the KREs seem to peak quite a bit higher than the E-heads (4000-4100 rpm) that I typically see. Is the Road Paver on 112 or 114 LSA? What is the converter stall and how streetable is it? Nice combo.

[chuckies76ta]

Originally Posted by tpssonic

chuckies76ta:

Very nice numbers. At what rpm does the 455 make peak hp? Peak torque?

Is the 236/245 on a 112 LSA? It seems like the peak torque (4500) is a bit higher than I've see for the OF cam, but the KREs seem to peak quite a bit higher than the E-heads (4000-4100 rpm) that I typically see. Is the Road Paver on 112 or 114 LSA? What is the converter stall and how streetable is it? Nice combo.

I'll try find the dyno sheet for the 455. Both cams are on 112 LSA. The converter is a 10" and flashes to around 3000 off the line just with foot braking. It probably stalls around 2k when driving normally.. The engine is very street-able. Makes 12 inch vacuum. The thing is a beast when when you get into it.

Thanks
Charles

[Firebob]

Will, thanks for the tq/stroke/CID 101.
Charles, very nice numbers. Thanks for posting a real-time comparison.

[AdamIsAdam]

this is great reading. I'm always amazed at the level of expertise here. THANKS FOR SHARING! (that's my Thanksgiving speech for the day

[HWYSTR455]

Originally Posted by chuckies76ta

I'll try find the dyno sheet for the 455. Both cams are on 112 LSA. The converter is a 10" and flashes to around 3000 off the line just with foot braking. It probably stalls around 2k when driving normally.. The engine is very street-able. Makes 12 inch vacuum. The thing is a beast when when you get into it.

Thanks
Charles

Very close to the cam I used to have in the LeMans, which was a Crower solid roller 247/254 that I had cut on a 114 (113.5 to be exact). It had 12-14" of vacuum, totally streetable, and, as you put it, a beast. Power brakes and AC, 310 e-heads.

.

[tpssonic]

10.90s pushing 3700 lbs. and streetable? Yes, I would say that is very impressive. HWYSTR455: that engine with some sniff as well? Woof, I would drive that daily. Yes Adam, I have learned a ton from all these guys in this thread- no doubt about that. They are invaluable sources.

Tony

[grandville455]

I ran pretty much the same as chuck, except the smaller sd 290 heads/ with victor and 1050 dom. I had a 9" 4600 stall and 4.10's and it is still very streetable, never over heats etc, runs mid 10's at over 126, best was 126.49. The trans was taken apart for a inspection after 600 passes and it looked perfect! nothing burnt etc, pump looked like new and it only used the stock paper frictions! I upgraded to better clutches now in the intermediate for next year. You cant go wrong with the old faithful or road paver IMO.

[HWYSTR455]

Originally Posted by tpssonic

10.90s pushing 3700 lbs. and streetable? Yes, I would say that is very impressive. HWYSTR455: that engine with some sniff as well? Woof, I would drive that daily. Yes Adam, I have learned a ton from all these guys in this thread- no doubt about that. They are invaluable sources.

Tony

I had a brand new NX Hitman Plus system on it, peremeter plate type, remote bottle valve, transducer bottle heater, and the NX bottle blanket, and never filled the bottle. It didn't need it! Ring gaps were cut for up to a 300hp shot, but like I said, it didn't need it.

Have over $1300 in the N2O setup, had it on egay twice for $650 and $575, not one nibble.

http://forums.maxperformanceinc.com/...d.php?t=764452

.

[GOAT WHORE]

Originally Posted by chuckies76ta

I have a 400 stroker in my T/A and my wife's 68 F/B is a 455 stroked.
The 400 dynoed at 560 h/p and 580 torque, The 455 dynoed at 590 h/p and 600 torque. Both have same KRE D-port heads from SD Performance.
Both engines have SD Performance cams. The 400 has hydraulic lifters with 236/245.
The 455 has solid lifters with 246/252.

My wife has run a best of 10.90 with her car weighting 3700 pds, Th400, 3.24 gear, and full 3" exhaust.

Charles

What is the cid on both engines?

[tpssonic]

HWYSTR455: pm sent

[chuckies76ta]

Originally Posted by GOAT WHORE

What is the cid on both engines?

The 400 stroked is .030 with a 4.25 crank, and the 455 is .030 over with a 4.25 crank, so I believe 461 and 468 cubes.

The intakes are Torker 2, and 950 Quickfuel carbs. The heads are 305 cfm. Both heads and intakes were done by Dave at SD performance.

Charles

[Will]

I love reading about combos like your wife's, Chuckies76ta. 10s with 3.24 rear gears? That's badass! ;-)

Gives me hope that when I get around to building another 4" stroke combo for my Formula that I'll be able to get into the 11s like I should have before.

paul s. - that's a very interesting factoid... I wonder why 250 fps is the magic number?

[chuckies76ta]

My mistake on the rear gear.. The 68 Firebird has 3.42 rear gear..

Thanks
Charles

[Will]

Well, that's still pretty streetable and I bet it wouldn't slow down all that much with a 3.23. Still very impressive!

[chuckies76ta]

Thanks guys..

Here's the dyno sheet from my Wife's 68 Firebird engine. I guess I'm a little off on the H/P. It's 588 and 600 torque. This engine has solid rollers on a hydraulic cam. Both engines have 1.5 ratio rockers.

Charles

[tpssonic]

Hmmm, I thought the Road Paver-cammed engine would have peaked at a noticeably higher peak hp/torque rpm as opposed to the OF-cammed engine due to the increased I and E durations. Were these tested on the same dyno with the same fuel? How about compression/ignition timing and air/fuel mixtures in both engines-were they similar? How about engine vaccuum on the OF-cammed engine? Hydraulic and solid lifter comparison? So many questions...There is a lot to be gleaned from the comparisons of these two engines. That is one honey of a powerplant (actually, they both are). Way cool. Kudos and Happy Thanksgiving. In the Poncho department, you have much to be thankful for. I can imagine at the very first Thanksgving the our native Americans would have been very happy to have exchanged food, hand-made textiles, and other items for your "great many horses". You and your Bride would have been coveted back then. Well, just a thought, anyway...

[AdamIsAdam]

Don't forget about the ties between Pontiac and Indians